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Geothermal Arrives at UNL's Whittier Remodel
"This is truly a sustainable, efficient geothermal system," said Marty Kasl, mechanical engineer with the Lincoln-based Engineering Technologies Inc., the group that designed the Whittier geothermal system. "When complete, this green design will be about 30 to 35 percent more efficient than state energy codes."
Similar to heat pumps currently used in homes (but on a larger scale), the Whittier geothermal system is powered by a well field of 233 holes, each drilled 300 feet deep. Each hole contains two one-inch tubes, which are connected by a specialized valve at the bottom. The tubes from each well are connected to main feeder lines running north and south through the rows of wells. One end of the tube draws water into the ground; the other funnels water back into the heating/cooling system in Whittier.
Ted Weidner, assistant vice chancellor for Facilities Management and Planning, said around 500 pipes enter Whittier's basement and go into a header; then the water flows into the heat pumps.
Two massive heat pumps will be in a control room between Whittier and the Child Care facility - the same area that housed Whittier's "vintage" early 1900s boiler system. The heat pumps draw heat from the water in the winter and chill in the summer, with air handling units providing temperature controls to the building. The water goes back to the well field, regains the 55 to 57 degree temperature, and makes return trips through the system.
"Whittier is about as far away from the central utility plant as you can get and a quarter of a mile from our closest steam or chilled water line," said Weidner. "To install a steam or chilled water line to Whittier would not have been cost-effective."
The geothermal system is projected to save between $30,000 and $35,000 per year on the UNL utility bill. Weidner said it is projected to pay for itself in about 20 years. Kasl said the system (with annual maintenance) is engineered for about 50 years of use.
A parking lot will cover the well field's holes and connecting tubes, manufactured in Kearney, making the system out of sight but not out of mind. Displays inside the building's entry will show how much energy the building is consuming.
"We're proud of the fact that we are striving to make Whittier as energy efficient as we can," said Weidner, "and we want people to take note of our efforts."